Method for resolving emulsions in enhanced oil recovery operations

ABSTRACT

Disclosed and claimed is a method of demulsifying an emulsion comprising water and oil. The method comprises adding an effective amount of a composition comprising at least one substantially fully quaternized ammonium adduct of polyephalohydrin that has a molecular weight from about 500 Da to about 2,500 Da.

FIELD OF THE INVENTION

This invention relates generally to the field of enhanced oil productionand recovery. More specifically, the invention relates to the field ofrecovery of crude oil from produced emulsions of surfactant-polymerenhanced oil recovery floods. The invention has particular relevance tothe use of quaternary ammonium salt adducts of polyepihalohydrinpolymers to resolve such emulsions.

BACKGROUND OF THE INVENTION

The production of crude oil from reservoirs typically results insignificant quantities of non-produced crude oil remaining in thereservoir. After primary oil recovery has been performed, secondaryrecovery (typically involving water injection), is commonly used toproduce trapped oil. Frequently, much oil remains in the reservoir andtertiary recovery operations have been developed to produce theremaining oil. Most tertiary recovery methods for recovering suchremaining crude oil include surfactant-polymer enhanced oil recoveryfloods, such as injecting a combination of surfactants and polymers inbrine solutions into the reservoir. Other methods for enhanced oilrecovery may include gas injection, chemical injection, ultrasonicstimulation, microbial injection, and thermal recovery. If the oilrecovered using enhanced oil recovery floods cannot be efficientlytreated (e.g., the emulsion broken into dry oil and clean water), thenmost if not all oil producers will be reluctant to conduct chemicalfloods in favor of other less aggressive and lower recovery processes.

Results of such conventional methods include a produced emulsion thattypically contains crude oil, water, surfactant, and polymer. Drawbacksinclude difficulties in separating the emulsion into clean water and dryoil for efficient recovery of the crude oil and proper disposal of thewater in an environmentally safe manner. Heat has been used to aid inresolving such emulsions but is not economical due to the large amountsof water involved. Solvent extraction is disclosed in U.S. Pat. No.4,559,148, “Method of Extracting and Reutilizing Surfactants fromEmulsions,” but is also not practical due to the large capitalinvestment and flammable solvent handling issues.

Consequently, there is a need for improved methods of resolving crudeoil and water emulsions. Additional needs include improved methods fordemulsifying the produced emulsion to produce a clean separation of thecrude oil and water.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention provides a method for resolvingemulsions produced through an enhanced oil recovery process. In anaspect, the method includes adding a composition comprising at least onequaternary ammonium adduct of polyepihalohydrin.

In an aspect, this invention meets the previously unmet need ofefficiently demulsifying an emulsion comprising water and oil. Theemulsions applicable in the method of the invention are preferablyderived from an enhanced oil recovery process, though the method hasequal applicability to any emulsions encountered in the art.

It is an advantage of the invention to provide a novel method ofresolving an emulsion comprising oil and water.

It is another advantage of the invention to provide a novel method ofefficiently resolving an emulsion comprising oil and water that wasderived from an enhanced oil recovery process.

It is yet another advantage of the invention to provide a novel methodof resolving an emulsion resulting from a chemical enhanced oil recoveryflood comprising oil and water to produce dry oil and clean water.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter that form the subject of the claims of the invention. Itshould be appreciated by those skilled in the art that the conceptionand the specific embodiments disclosed may be readily utilized as abasis for modifying or designing other embodiments for carrying out thesame purposes of the present invention. It should also be realized bythose skilled in the art that such equivalent embodiments do not departfrom the spirit and scope of the invention as set forth in the appendedclaims

DETAILED DESCRIPTION OF THE INVENTIOIN

This invention comprises a method of treating an emulsion comprising oiland water derived from an oil recovery process. A preferred area of themethod of the invention are emulsions derived from enhanced oil recoveryprocesses where oil remaining in a reservoir after conventional recoverymethods have been exhausted is produced through, for example, apolymer-surfactant flood. It should, however, be appreciated that themethod of the invention has equal application to emulsions derived fromany conventional or enhanced oil recovery operation. The objective ofthe present invention is to provide a method of resolving emulsionsresulting in dry oil and clean water.

The emulsion produced from an enhanced oil recovery process is typicallystabilized with surfactants and polymers. The method of the invention isapplicable to any enhanced or tertiary oil recovery process. Exemplarymethods of producing oil through such enhanced oil recovery processesare disclosed in U.S. Pat. Nos. 4,293,428, “Propoxylated EthoxylatedSurfactants and Method of Recovering Oil Therewith” and 4,018,278,“Surfactant Oil Recovery Process Usable in High Temperature Formations.”U.S. Pat. No. 3,591,520 discloses the process of breaking anoil-in-water emulsion with a blend of high molecular weight quaternaryadducts of polyepihalohydrin (MW>3000) and 10% zinc chloride at a ratioof at least 2.5 to 1 of metal salt to adduct. U.S. Pat. No. 3,320,317discloses the use of partial quaternary ammonium adducts ofepichlorohydrin having molecular weight from about 600 to about 100,000as flocculating agents for improving the sedimentation of sewage solids.

In the method of the invention, emulsions are treated by a compositioncomprising low molecular weight (weight average molecular weight fromabout 500 Da to about 2,500 Da) substantially fully quaternized adductsof tertiary amines and polyepihalohydrin (>99% quaternized) to demulsifyemulsions produced, for example, by surfactant-polymer enhanced oilrecovery floods and recover dry oil and clean water. In a preferredembodiment, zinc chloride is substantially absent from the composition.The composition is more preferably free of zinc chloride. In soursystems, zinc chloride reacts with hydrogen sulfide presence in thecrude oil to form zinc sulfide which can cause stable emulsion (i.e.,rag layer between oil and water interface) and foul the separationvessels. High molecular weight quaternary ammonium adducts ofepihalohydrin and partial quaternary ammonium adducts of epihalohydrin(particularly epichlorohydrin) were found to be less effective (seeexamples below) in the tested emulsions caused by chemical enhanced oilrecovery floods. In such embodiments, the produced emulsions typicallycontain at least water, crude oil, surfactants, and polymers. Additionof the composition to the produced emulsion separates the oil and waterphases. In some embodiments, the separation is a clean separation of oiland water. A clean separation generally refers to dry oil with less thanabout 1% total sediment and water, a good interface with sharpseparation between oil and water, and clean water with less than about300 parts per million (ppm) residual oil. The composition is added tothe emulsion by any suitable method. (See e.g., Z. Ruiquan et al.,“Characterization and demulsification of produced liquid from weak baseASP flooding,” Colloids and Surfaces, Vol. 290, pgs 164-171, (2006);U.S. Pat. Nos. 4,374,734 and 4,444,654).

In an embodiment, the composition of the invention includes watersoluble quaternary adducts of polyepihalohydrin having molecular weightsof from about 500 to 2,500 which have the general formula:

In the general formula, each R independently represents methyl or ethyland z ranges from about 4 to about 22. X is a halide selected fromfluoride, chloride, bromide, iodide, astatide, and any combinationthereof. In a preferred embodiment, X is chloride and z is from 4 to 7.More preferably z is 6. In a further preferred embodiment, X ischloride, z is 6, and at least one R is methyl. More preferably, each Ris methyl.

These materials may be prepared by any suitable method. Generally, thematerials are prepared by reacting a polyepihalohydrin withtrimethylamine or triethylamine at a molar ratio of 1:1.1 attemperatures from about 100° C. to 150° C., preferably at a temperatureof about 100° C. If the quaternizing amine is volatile such astrimethylamine, the reaction is typically carried out in a closed vesselunder the pressure such as an autoclave. The molecular weight of thepolyepihalohydrin can be controlled by the epihalohydrin to water ratioin the presence of boron trifluoride as a catalyst. A preferred catalystfor preparation of the polyepihalohydrins of the invention is borontrifluoride, rather than the more common organoaluminum catalyst (Seee.g., U.S. Pat. No. 3,591,520). The main advantage of using the borontrifluoride catalyst is that a smaller amount of catalyst is used.

The disclosed polyepihalohydrin composition may have any desirableamount of active material. In an embodiment, the composition has fromabout 30 wt % to about 90 wt % active material. Alternatively, thecomposition has from about 30 wt % to about 60 wt % or from about 40 wt% to about 70 wt %, and further alternatively the composition has fromabout 50 wt % to about 90 wt % active material. The composition is addedto the emulsion in any suitable amount.

Embodiments further include a composition having the disclosedpolyepihalohydrin and a solvent. The solvent may be any solventsuitable, for example, for dissolving or suspending the quaternaryammonium adducts of polyepihalohydrin. In embodiments, the solvent iswater, alcohol, an organic solvent, or any combination thereof. Thealcohol may include any alcohol suitable as a solvent and for use withoil recovery operations. Without limitation, examples of suitablealcohols include glycol, isopropyl alcohol, methanol, butanol, or anycombination thereof. According to an embodiment, the organic solventincludes aromatic compounds, either alone or in any combination with theforegoing. In an embodiment, the aromatic compounds have a molecularweight from about 70 to about 400, alternatively from about 100 to about200. Without limitation, examples of suitable aromatic compounds includetoluene, xylene, naphthalene, ethylbenzene, trimethylbenzene, and heavyaromatic naphtha (HAN), other suitable aromatic compounds, and anycombination of the foregoing. It is to be understood that the amount ofquaternary ammonium adducts of polyepihalohydrin in the composition inrelation to the solvent may vary in some embodiments depending uponfactors such as temperature, time, and type of surfactant. For instance,without limitation, a higher ratio of a quaternary ammonium adduct ofpolyepihalohydrin to solvent may be used if a faster reaction time isdesired.

The composition may also be added to the emulsion in any suitableamount. In an embodiment, the composition is added in an amount fromabout 50 ppm to about 20,000 ppm, based on actives and total emulsionvolume. In alternative embodiments, from about 100 ppm to about 10,000ppm of the surfactant, further alternatively from about 200 ppm to about10,000 ppm surfactant, and further alternatively from about 200 ppm toabout 500 ppm surfactant is added to the emulsion, based on actives andtotal emulsion volume.

In embodiments, the disclosed polyepihalohydrin composition is used inconjunction with other surfactants or additives. These other surfactantsor additives may be added as part of the same composition or as aseparate composition and may be added simultaneously or sequentially.For example, the composition may be added to the produced emulsion withone or more additional components selected from a cationic surfactant, anonionic surfactant, an amphoteric surfactant, or any combinationthereof.

Without limitation, the cationic surfactants include alkyl ammoniumhalide surfactants. Representative, cationic surfactants include anycombination or at least one of an alkyl trimethyl ammonium halide, analkyl dimethyl benzyl ammonium halide, and one or more imidazoliniumhalides. Molecular weights of such quaternary surfactants are in therange of about 200 to about 700, alternatively from about 250 to about500. The alkyl trimethyl ammonium halide has an average alkyl chainlength of C₆ to C₁₆, alternatively C₆ to C₁₀, and alternatively C₁₂ toC₁₈, and further alternative of C₈.

Without limitation, examples of suitable polymeric nonionic surfactantsinclude polysorbates, fatty alcohols such as cetyl alcohol and oleylalcohol, copolymers of polyethylene oxide, copolymers of polypropyleneoxide, alkyl polyglucosides such as decyl maltoside, alkylphenolpolyethylene oxide, alkyl polyethylene oxide, and ethoxylatedpropoxylated alkyl phenol-formaldehyde resin chemistry. The polymericnonionic surfactant is typically dissolved or suspended in a solvent.Any solvent suitable for dissolving or suspending a polymeric nonionicsurfactant may be used. Without limitation, examples of suitablesolvents include water, ether, alcohol, toluene, xylene, heavy aromaticnaphtha (HAN), other suitable organic solvents, or any combinationthereof. The alcohol may include any alcohol suitable for use with oilrecovery and for dissolving the polymeric nonionic surfactant. In anembodiment, the polymeric nonionic surfactant is dissolved or suspendedin a solvent.

Without limitation, amphoteric surfactants useful in the composition ofthe invention include betaines, alkylamionpropionic acids, N-acylglycinates, or any combination thereof. Any suitable betaine for use asa surfactant in the produced emulsion may be used. Without limitation,examples of suitable betaines include capryllcapramidopropyl betaine,cocobetaine, cocamidopropylbetaine, octyl betaine, caprylamidopropylbetaine, or any combination thereof. The N-acyl glycinate is preferablytallow dihydroxyethyl glycinate.

In an embodiment, the composition and the one or more additionalcomponents are added to the produced emulsion in a weight ratio ofcomposition to polymeric nonionic surfactant from about 9:1,alternatively from about 1:1. In embodiments, the composition and, forexample, polymeric nonionic surfactant are added about simultaneously(either as separate formulations or as part of the same formulation) orsequentially to the produced emulsion. Without being limited by theory,simultaneous addition to the produced emulsion of the composition and apolymeric nonionic surfactant generally provide improved quality ofseparated oil and aqueous phases. For instance, the simultaneousaddition to the produced emulsion of the disclosed composition and waterwith a polymeric nonionic surfactant dissolved in an organic solventimproved the quality of the separated oil and aqueous phases.

The foregoing may be better understood by reference to the followingexamples, which are intended for illustrative purposes and are notintended to limit the scope of the invention.

Example 1

9 grams of water (0.50 mole) was added to a 500 ml 3-neck reactor flask,and then sparged with nitrogen for 15 minutes. 2 ml of boron trifluoridewas slowly added and the mixture was heated to 60° C. When thetemperature was reached 60° C., the heater was removed and 231.3 g ofepichlorohydrin (2.5 mole) was slowly added with stirring. This reactionwas exorthemic and the temperature was kept between 90 and 100° C. withthe use of an ice bath. After complete addition of epichlorohydrin, thereaction was held for another 1 hour at 90° C., and then for 30 minutesat 110° C. The reactor was then cooled to 40° C. and thepolyepichlorohydrin was transferred to an autoclave for quarternization.About 361.22 grams of 45% trimethylamine aqueous solution (2.75 mole oftrimethyamine) was added to polyepichlorohydrin. The blend was heated to100° C. for 24 hours. The composition was clear without sediments. Thetheoretical molecular weight is about 780 g/mole and this product isnamed Composition A.

Example 2

Cocktails 1 and 2 as shown in Table 1 are fluids that were injected intothe reservoir to enhance oil recovery. The emulsion was produced in thelab by mixing either Cocktails 1 or 2 with the oil at 90:10 or 50:50 byweight, respectively, under a high shear via the Silverson L4RT Mixer at5,000 rpm for 2 minutes. The produced emulsion was then subjected to thedescribed testing. Cocktails 1 and 2 contained a very low concentrationof the surfactant that was used to achieve ultra low interfacial tensionbetween the trapped oil and the injection fluid/formation water. Theultra low interfacial tension also allowed the alkali present in theinjection fluid to penetrate deeply into the formation and contact thetrapped oil globules. The alkali present in the fluids (e.g., Na₂CO₃)then reacted with the acidic components in the crude oil to formadditional surfactant in-situ to continuously provide ultra lowinterfacial tension and free the trapped oil. In the alkaline surfactantpolymer (“ASP”) Process, polymer present in the injection fluid was usedto increase the viscosity of the injection fluid, minimize channeling,and provide mobility control. These surfactant and polymer moleculeshave a tendency to adsorb at the oil droplet, thereby, stabilizing theemulsions.

The tests that produced the data in Tables 2 and 4 were conducted ingraduated six ounce prescription bottles to allow for rapid water dropreadings. All bottles used 100 ml of emulsion. After pouring theemulsion followed by chemical addition, the bottles were allowed toreach the desired temperature via a water bath. Upon reaching thedesired temperature, the samples were shaken via a mechanical shaker andthen returned to the water bath. Water drop readings were recorded inmillimeters. The values were also used to gauge emulsion stability,where a faster water drop indicated lower emulsion stability. As can beseen in Table 2, the present invention is very effective at resolvingthe emulsion. Conventional demulsifiers such as ethoxylated propoxylatedalkyl phenol-formaldehyde resins and alkylphenol polyethylene oxide werefound not to be effective under the tested experimental conditions.Also, cationic surfactant such as alkyldimethylbenzyl ammonium chloriderequired a much higher dosage (7,000 ppm) as compared to 3,000 ppm forthe tested composition of the present invention (i.e., Composition A).

TABLE 1 Water chemistry for ASP flood Species Cocktail 1 Cocktail 2 NaCl(g/L) 3.115 3.115 CaCl₂•2H2O (g/L) 0.096 0.096 MgCl₂•6H2O (g/L) 0.0930.093 NaHCO₃ (g/L) 1.310 1.310 KCl (g/L) 0.054 0.054 Na₂SO₄ (g/L) 0.2360.236 Surfactant A, ppm 1,500 — Surfactant B, ppm 1,500 — Surfactant C,ppm — 1,500 Surfactant D, ppm — 1,500 Diethylene glycol monobutyl 10,00010,000 ether (DGBE), ppm Na₂CO₃, ppm 10,000 10,000 Polyacrylamide, ppm1,500 1,500

The demulsification was performed at 60° C. using Composition A asdescribed in Example 1.

TABLE 2 Bottle test results of demulsification of an Alkaline SurfactantPolymer (ASP) process Water Drop, (ml per 100 ml emulsion) ASP DoseOver- solution Oil Cut (ppm) 30 min 1 hr 2 hrs 4 hrs night Cocktail 110% Oil Cut 1,000 90 90 90 90 90 2,000 90 90 90 90 90 3,000 90 90 90 9090 4,000 90 90 90 90 90 50% Oil Cut 500 0 0 18E* 30E 30E 1,000 0 20 4042 45 2,000 5 38 42 43 45 3,000 40 42 42 42 45 4,000 49 49 49 49 49Cocktail 2 10% Oil Cut 500 92 90 90 90 90 1,000 92 90 90 90 90 2,000 9190 90 90 90 50% Oil Cut 1,000 0 0  0  0 30E 2,000 42 43 43 45 45 3,00046 45 46 46 45 4,000 46 46 46 46 46 5,000 47 46 46 46 46 Untreated 10%Oil Cut 0 0 0 78E —  9 *Water drop number with an “E” designationindicates the water phase is oil-in-water emulsion (dirty water)

TABLE 3 Water chemistry for Surfactant Flood Species Amount NaCl (g/L)4.81 CaCl₂•2H₂O (g/L) 1.00 MgCl₂•6H₂O (g/L) 2.01 NaHCO₃ (g/L) 3.99Na₂SO₄ (g/L) 0.13 Petrostep S13D 5,000 (anionic surfactant) (ppm)(84.32% active)

Table 3 lists the injection fluid constituents for the composition usedin the surfactant flood. The emulsion was produced in the lab by mixingthe injection fluid with the oil at 75:25 wt/wt, respectively, byshaking the bottle containg the mixture mechanically for 10 minutes. Thedemulsifier was added to the above emulsion and the bottle was againshaken for 2 minutes. The demulsification was performed at 25° C. usingComposition A and alkyldimethylbenzyl ammonium chloride using thetesting method described previously. In the test results presented inTable 4, oil drop readings were recorded (as opposed to water dropreadings above) and were converted to the percentage of oil content. Ascan be seen in Table 4, the present invention (e.g., Composition A)outperformed the alkyldimethylbenzyl ammonium chloride (Composition B)as indicated by a higher value for oil drop and much cleaner water andalso yielded a dry oil as indicated by small values of bottom sedimentor settlings (BS) and slug. The calculations and definitions of thesevalues are discussed below.

Following the water drop readings, the resolved or partially resolvedoil from each bottle was analyzed for water content. Using a syringewith a needle, a small portion of the oil (about 6 ml) was withdrawn.This aliquot of oil was added to a graduated API centrifuge tubecontaining an equal volume of an aromatic solvent and the contents wereshaken by hand. Following centrifugation, the percent residual emulsion,typically referred to BS, was noted for each bottle. After recording BSvalues, alkyl sulfonate surfactant (a chemical known to resolve theremaining emulsion) was added to the centrifuge tube. Such chemicals aregenerally called “slugging or knockout chemicals” and are typically lowmolecular weight sulfonate-based materials. After slugging, the tube wasagain shaken and centrifuged as previously described. The BS was thuscompletely eliminated and only water remained in the bottom part of thetube. The slug grindout number is reported as a percentage. Smallervalues of BS and slug indicate drier oil.

TABLE 4 Bottle test results of demulsification of a surfactant floodemulsion with 25% oil cut Oil drop, % Thief Grindout Treatment ppm 0.5hr 1 hr 2 hr 4 hr 20 hr BS Slug Untreated 0 0  8 16 52 72 15.2 6.0 Comp.A 2,000 100*  100 100  100  100  0.8 0.8 Comp. B 2,000  76**   84** 84**  84**  84** 0.8 0.8 *Clean water **Dirty water

Table 4 lists an example of the injection fluid used forsurfactant-polymer flood (SP). The procedures for making the emulsionand demulsification were described previously. Petrostep is availablefrom Stepan Company located in Northfield, Ill. and Flopaam is availablefrom SNF Floerger located in Andrezieux, France (trademarks are propertyof the respective owners).

TABLE 4 Produced Brine Formulations to make 100 g Brine forSurfactant-Polymer Flood brine NaCl (grams) 1.0 CaCl₂•2H₂O (grams)0.1834 (Ca++, ppm) 500 FLOPAAM ® 3330S 0.12 (grams), 8 MM MW HPAMPETROSTEP ® S-1 0.9458 (15.86% active; grams*) PETROSTEP ® S-2 0.2223(22.49% active; grams*) Iso-butyl alcohol (R-3041; grams) 0.4 *weight ofsurfactants as received

Table 5 shows the demulsification results conducted at 25° C. In thisTable, Compositions C, D, and E have the same chemistry as Composition A(see Example 1) but different molecular weights. The theoreticalmolecular weights for Compostions A, C, D, and E are 780 g/mole, 2,300g/mole, 1,500 g/mole, 320 g/mole, respectively. Composition F is apyridinium benzyl quat and Composition G is a high molecular weightpolydiallyldimethylammonium chloride-polyacrylic acid copolymer.Compositions A, D, and E broke the emulsion quickly (15 minutes), gaveclean water after the emulsion was resolved, and produced dry oil. Othercompostions took longer to break the emulsion, gave dirty water or wetoil.

TABLE 5 Bottle test results of demulsification of a surfactant-polymerflood emulsion with 30% oil cut. Unless otherwise noted, the waterseparated from the emulsion was clear and clean ppm Water drop (ml/100ml emulsion) Thief Grindout Product Actives 15 min 1 hr 2 hr 3 hr B.SSlug Untreated 0 20* 50* 60* 60* 28 34 Comp. A 200 65 69 69 70 0.6 0.6Comp. B 210 68** 68** 70** 70** 0.4 0.4 Comp. C 200 65** 69 69 69 0.80.8 Comp. D 200 66** 69 69 70 0.8 0.8 Comp. E 200 20* 40* 60* 60** 13 24Comp. F 200 65** 65** 68* 65* 0.6 0.2 Comp. G 210 10* 39* 60* 62** 11 25*the water is dirty and rag layer (emulsion at the oil/water interface)is present **the water is dirty but no rag layer is formed

All of the compositions and methods disclosed and claimed herein can bemade and executed without undue experimentation in light of the presentdisclosure. While this invention may be embodied in many differentforms, there are described in detail herein specific preferredembodiments of the invention. The present disclosure is anexemplification of the principles of the invention and is not intendedto limit the invention to the particular embodiments illustrated.

Any ranges given either in absolute terms or in approximate terms areintended to encompass both, and any definitions used herein are intendedto be clarifying and not limiting. Notwithstanding that the numericalranges and parameters setting forth the broad scope of the invention areapproximations, the numerical values set forth in the specific examplesare reported as precisely as possible. Any numerical value, however,inherently contains certain errors necessarily resulting from thestandard deviation found in their respective testing measurements.Moreover, all ranges disclosed herein are to be understood to encompassany and all subranges (including all fractional and whole values)subsumed therein.

Furthermore, the invention encompasses any and all possible combinationof some or all of the various embodiments described herein. Any and allpatents, patent applications, scientific papers, and other referencescited in this application, as well as any references cited therein, arehereby incorporated by reference in their entirety. It should also beunderstood that various changes and modifications to the presentlypreferred embodiments described herein will be apparent to those skilledin the art. Such changes and modifications can be made without departingfrom the spirit and scope of the invention and without diminishing itsintended advantages. It is therefore intended that such changes andmodifications be covered by the appended claims.

1. A method of demulsifying an emulsion comprising water and oil, themethod comprising adding an effective amount of a composition comprisingat least one substantially fully quaternized ammonium adduct ofpolyepihalohydrin and substantially free of zinc chloride, wherein saidadduct(s) have a weight average molecular weight from about 500 Da toabout 2,500 Da.
 2. The method of claim 1, wherein the quaternaryammonium adduct(s) of polyepihalohydrin are fully quaternized.
 3. Themethod of claim 1, wherein the composition is free of zinc chloride. 4.The method of claim 1, wherein the substantially fully quaternizedammonium adduct(s) of polyepihalohydrin is formed by reacting apolyepihalohydrin with trimethylamine or triethylamine at a molar ratioof 1:1.1 and at temperatures from about 100° C. to 150° C.
 5. The methodof claim 1, wherein the quaternary ammonium adduct(s) ofpolyepihalohydrin are prepared in the presence of a boron trifluoridecatalyst.
 6. The method of claim 1, wherein the quaternary ammoniumadduct(s) of polyepihalohydrin have general formula:

wherein each R is independently methyl or ethyl and z ranges from about4 to about 22
 7. The method of claim 6, wherein X is selected from thegroup consisting of: fluoride, chloride, bromide, iodide, astatide, andany combination thereof.
 8. The method of claim 6, wherein X ischloride.
 9. The method of claim 6, wherein z is
 6. 10. The method ofclaim 6, wherein at least one R is methyl.
 11. The method of claim 6,wherein each R is methyl.
 12. The method of claim 1, wherein thecomposition comprises from about 30 to about 90 wt % active material.13. The method of claim 1, wherein the composition further comprises anorganic solvent, water, and any combination thereof.
 14. The method ofclaim 11, wherein the organic solvent comprises an alcohol, an ether, anaromatic compound, or any combination thereof.
 15. The method of claim1, wherein the effective amount of the composition comprises from about50 ppm to about 20,000 ppm, based on actives and total emulsion volume.16. The method of claim 1, further comprising adding a component to theemulsion, wherein the component is selected from the group consisting ofa polymeric nonionic surfactant, a polymeric cationic surfactant, abetaine, and any combination thereof.
 17. The method of claim 16,wherein the component and the composition are added about simultaneouslyto the emulsion.
 18. The method of claim 1, wherein the emulsion is aproduced emulsion from an enhanced oil recovery operation.